Part (a)

Write the trimSilenceFromBeginning method that removes leading silence.

Solution

public void trimSilenceFromBeginning()
{
    int firstNonSilent = 0;
    while (firstNonSilent < samples.length && 
           Math.abs(samples[firstNonSilent]) <= limitAmplitude)
    {
        firstNonSilent++;
    }
    
    int[] newSamples = new int[samples.length - firstNonSilent];
    for (int i = 0; i < newSamples.length; i++)
    {
        newSamples[i] = samples[firstNonSilent + i];
    }
    samples = newSamples;
}

Part (b)

Write the limitAmplitude method that caps all values to a maximum.

Solution

public int limitAmplitude(int limit)
{
    int count = 0;
    for (int i = 0; i < samples.length; i++)
    {
        if (samples[i] > limit)
        {
            samples[i] = limit;
            count++;
        }
        else if (samples[i] < -limit)
        {
            samples[i] = -limit;
            count++;
        }
    }
    return count;
}

Key Concepts

Common Mistakes